A preliminary characterization of the tensile and fatigue behavior of tungsten-fiber/Waspaloy-matrix composite

A microstructural study and a preliminary characterization of the room temperature tensile and fatigue behavior of a continuous, tungsten fiber, Waspaloy-matrix composite was conducted. A heat treatment was chosen that would allow visibility of planar slip if it occurred during deformation, but would not allow growth of the reaction zone. Tensile and fatigue tests showed that the failed specimens contained transverse cracks in the fibers. The cracks that occurred in the tensile specimen were observed at the fracture surface and up to approximately 4.0 mm below the fracture surface. The crack spacing remained constant along the entire length of the cracked fibers. Conversely, the cracks that occurred in the fatigue specimen were only observed in the vicinity of the fracture surface. In instances where two fiber cracks occurred in the same plane, the matrix often necked between the two cracked fibers. Large groups of slip bands were generated in the matrix near the fiber cracks. Slip bands in the matrix of the tensile specimen were also observed in areas where there were no fiber cracks, at distances greater than 4 mm from the fracture surface. This suggests that the matrix plastically flows before fiber cracking occurs

Changes in Structure and Access to Post-Compulsory Education in European Community Countries: With Special Reference to Scotland and Denmark

SECTION I The research aims that guided this study's general development, and the limitations that these imposed, are given in chapter one. Some important changes in post-war European education are outlined and references made to the sections of the study where these perspective are amplified further. A short critical review is given of the contribution of comparative analysis in the study of educational systems and the use of case studies in the interpretation of general educational change. SECTION II Chapter two illustrates European cultural and social patterns and some implications that arise within education. It examines this cultural mosaic through linguistic and social variables because of the fundamental importance these have for learning and education. Other dimensions referred to are regionalism, centre-periphery models, cultural dominance, minority rights and mobility. The Arfe Report and other analyses of the diversity of European culture and educational provisions set important trends. After a review of European cultural and regional minorities, it is proposed that educational change in contemporary Europe should recognise four dimensions: 1) contributions of small education systems, 2) indigenous regional minorities, 3) immigrant minorities from ex-colonised countries requiring new types of education, and 4) the fragile, but growing, perception of Europe as a holistic entity. Chapter three illustrates the changing role of post-compulsory education by analysing the reorganisation of education systems in the Benelux countries and other small countries in Europe. The Benelux countries have established themselves as important actors in the development towards the European Single Market concept. At the same time, and despite highly complex educational systems, they have been in the forefront of changes in the 'privatisation' of education through market forces, which is interpreted in the study as a search for flexible responses to survival and change. It seems yet to be established whether the market-driven forces, operating at the upper-secondary and higher stages of a country's education system, can carry through permanent changes in European systems. Fundamental to this is the question of whether mechanistic change entrenched through monetary policy can affect the deeper structures of learning and curricula in the longer term. SECTION III Chapter four discusses several themes in Scottish education, especially the historical case for maintaining the 'democratic intellect' as a response to the need for flexible general education. It is proposed that the concept of the 'democratic intellect', which parallels the democratising element of the Danish notion of 'peoples enlightenment', can be accommodated into contemporary education through merging the 'academic' universities and 'vocational' central institutions. The case for more open access is based on comparing developments of selection and choice in Scottish post-compulsory with that of European and American education systems; the evidence presented shows that restricted access is still a dominating force, exercised through the twin notions of 'discipline' and 'disciplines', and controlled through financial policies of centralised governance. Chapter five introduces Danish education as a part of cultural and economic interchange within the Nordic region. Increasing educational mobility through the activities of the Nordic Council is described and related to the models of mobility established within the European Community. Through changes in Danish educational policy dating from 1982, a description is given of the transition from education informed by social-democratic values to those of conservative-liberal ideals, dominated by quality in education and based on monetary control of education which has similarities to developments in the Benelux Countries and the United Kingdom. One of the most important contributions to European education that Denmark has made is the concept of 'popular enlightenment'. The contribution of such a concept has in maintaining Danish educational traditions is discussed in the light of the contemporary policies of 'quality' and 'internationalism'. New routes to higher education through second chance programmes and the broad provision of adult education have maintained the traditions of Danish education, whilst absorbing the tendency to vocationalise and shorten higher education programmes. Overall, and in common with Scottish education, it is suggested that pressures of European market strategies have tended to produce quality control of education rather than quality in education. (Abstract shortened by ProQuest.)

Is There a Nexus Between Terrorist Involvement and Mental Health in the Age of the Islamic State?

The wave of Islamic State-linked terrorism experienced in the West over the past couple of years has rekindled debates surrounding mental disorders and terrorist engagement. A very preliminary survey by the authors found that out of 55 attacks in the West where the 76 individuals involved were possibly influenced by the Islamic State, according to media reports, 27.6% had a history of apparent psychological instability, a percentage comparable to that found in the general population. This figure is driven largely by individuals inspired by the Islamic State, as opposed to those directed by it, however. The percentage is likely overinflated for several noteworthy reasons, including poor reporting, low benchmarks, and the tendency to overuse mental health problems as a ‘silver-bullet’ explanation for terrorist involvement. The relationship is, in fact, far more complex than typically presented

There and Back Again: The Study of Mental Disorder and Terrorist Involvement

For the past forty years, researchers studied the relationship between mental disorder and terrorist involvement. The literature developed in four paradigms, each of which differs in terms of their empirical evidence, the specific mental disorders studied, and their conceptualizations of terrorist involvement. These paradigms have not, however, witnessed linear and incremental improvements upon one another. Although one paradigm has generally tended to dominate a temporal period, many false assumptions and incorrect interpretations of earlier work permeate into today’s discourse. This paper provides a history of the study of mental disorders and the terrorist. First, we briefly outline the core fundamental principles of the first two paradigms, The paper then outlines the core arguments produced by the seminal reviews conducted in paradigm three. We highlight how these findings were consistently misinterpreted in subsequent citations. We then highlight recent innovations in the study of terrorism and mental disorder since the various influential literature reviews of 1997-2005. We conclude by outlining how future research in this area may improve in the coming years by broadening our understanding of both terrorist involvement and psychopathology away from simple dichotomous thinking

A False Dichotomy? Mental Illness and Lone-Actor Terrorism

We test whether significant differences in mental illness exist in a matched sample of lone- and group-based terrorists. We then test whether there are distinct behavioral differences between lone-actor terrorists with and without mental illness. We then stratify our sample across a range of diagnoses and again test whether significant differences exist. We conduct a series of bivariate, multivariate, and multinomial statistical tests using a unique dataset of 119 lone-actor terrorists and a matched sample of group-based terrorists. The odds of a lone-actor terrorist having a mental illness is 13.49 times higher than the odds of a group actor having a mental illness. Lone actors who were mentally ill were 18.07 times more likely to have a spouse or partner who was involved in a wider movement than those without a history of mental illness. Those with a mental illness were more likely to have a proximate upcoming life change, more likely to have been a recent victim of prejudice, and experienced proximate and chronic stress. The results identify behaviors and traits that security agencies can utilize to monitor and prevent lone-actor terrorism events. The correlated behaviors provide an image of how risk can crystalize within the individual offender and that our understanding of lone-actor terrorism should be multivariate in nature

Psychological distress and terrorist engagement: Measuring, correlating, and sequencing its onset with negative life events, social factors, and protective factors

This article employs probability-based modelling to unpack the complex and multifaceted individual, social, and psychological processes that may provide psychological protection for individuals engaged with terrorist groups. We outline the predictors of the onset of psychological distress across two phases of terrorist involvement (pre-engagement and engagement). Using a dataset of 96 terrorist autobiographies, we conduct sequence analyses to pinpoint the onset of psychological problems and the experiences that preceded and followed this onset. The results demonstrate a complexity in the relationship between mental disorders and terrorist engagement, as well as the heterogeneity of the lived experience of “being” a terrorist. The experience of psychological distress was mediated by numerous factors and the combination of these factors. The evidence suggests that, in certain cases, individual and group resilience may be a protective factor when an individual faces negative experiences. The presence of protective factors may not be sufficient to explain why group-actor terrorists present with a lower than expected prevalence of mental disorder. Future work should examine whether experiences commonly viewed as risk factors may be more useful in examining the occurrence of psychopathology in terrorists

Mental Health Disorders and the Terrorist: A Research Note Probing Selection Effects and Disorder Prevalence

Recent research on lone-actor terrorism has found a high prevalence of mental health disorders amongst these offenders. This research note addresses two shortcomings in these existing studies. First, it investigates whether selection effects are present in the selection process of terrorist recruits. Second, it builds upon the argument that mental health problems and terrorist behaviour should not be treated as a yes/no dichotomy. Descriptive results of mental health disorders are outlined utilising a number of unique datasets

Assessing the behavioural trajectories of terrorists: The role of psychological resilience

Within studies critically examining terrorist behaviour, the examination of mental health has largely focused on the relationship with the movement towards terrorist involvement. The impact of engagement in terrorism upon mental health has rarely been studied. However, recent research has shown that there is an association between terrorist engagement and the occurrence of mental health problems across the spectrum of terrorist involvement. This work therefore expands on previous research, and disaggregates three discrete stages of terrorist involvement; pre-engagement, engagement, and disengagement, to critically examine the role of psychological resilience on mental health. To determine whether psychological resilience protects against the negative psychological repercussions of terrorist involvement, we undertake cluster analyses. Results indicate that there is a subset of actors who demonstrate psychological resilience, and appear to maintain their mental health despite their experiences during involvement in terrorism

Updating and organizing our knowledge of risk and protective factors for lone-actor terrorism

This chapter updates builds upon previous descriptive analyses of loneactor terrorists, their behaviours, ideological backgrounds and degrees of 'loneness'. It offers greater conceptual clarity, updated data and a more expansive set of variables from previous analyses. Individual vulnerability indicators examined here include potential indicators of cognitive susceptibility to moral change, and self-selection and social selection into radicalizing settings, notably membership of a social network containing one or more radicalized individual. We also examine exposure settings, attack-preparation behaviours and explore sub-set analyses of the data. The analyses informed by a Risk Analysis Framework which offers a multilevel, integrated meta-model of these events and allows for the synthesis of disparate findings. The analyses provide key insights into the behaviour of lone-actors, which could inform intelligence gathering and investigative practice, as such analyses already do in other crime prevention domains